<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=\, initial-scale=1.0">
    <title>Document</title>
    <script src="./base.js"></script>
</head>
<body>

<button id="btn" >点我看时间</button>
<script>
    var btn=document.getElementById('btn')
    btn.onclick=function(){
        document.write(Date())
    }
</script>
</body>
</html>